Water-cooled door for furnaces.



PATENTED AUG. 27, 1907'.

L. L. KNOX. WATER 000mm DOOR FOR FURNACES.

APPLICATION FILED MAY 23. 1904.

Milliiillilil" WITNESSES INVENTOR UNITED STATES PATENT OFFICE,

LUTHER L. KNOX, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR OF ONE-FOURTH TO MONT MURRAY AND ONE-FOURTH TO H. E. WEISKOPF, OI" PI'JTSBURG, PENNSYLVANIA.

WATER-COOLED. DOOR FOR FURNACES.

Specification of Letters Patent.

. Patented Aug. 27, 1907.

To all whom it may concern:

Be it known that I, LUTHER L. Knox, of Pittsburg,

Allegheny county, Pennsylvania, have invented a new and useful Water-Cooled Door for Furnaces, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which Figure 1 is a front elevation of my improved door; Fig. 2 is a vertical central section; Fig. 3 is a top plan view partly broken away; and Figs. 4, 5, 6 and 7 are views similar to Figs. 1, 2 and 3 respectively, showing a modified form.

My invention relates to the class of water-cooled furnace doors, and is designed to provide a simple andefficient construction in which the door may be cast in 1 two or more pieces removably secured together. It is also designed to provide for water connections between the plurality of parts by which water circulation may be maintained continuously through said parts.

In the drawing, referring to the form of Figs. '1, 2 and 3, 2 represents a hollow door body cast in one piece and closed on all its edges. The other part of this twopart door consists of a single hollow rim casting made up of the checks 3, 3 and top and bottom rails 4 and 5. I have shown the body 2 as of a slightly larger size than the space between the rails and checks, the door fitting against the front of the cheek and rail casting. It may, however, be made slightly smaller and fitted into the front portion of this space if desired.

The body casting is shown as secured to the check and rail casting by perforated lugs 6 projecting laterally from the body casting, and secured by bolts 7, the heads of which slip between hooked lugs 8 arranged in pairs with an opening or slot between them. I have shown eight of these bolt connections, but their number and position may be varied, and other forms of connections may be used. l

The water enters one upper corner of the rim-casting through a pipe 9 screwed into the top. It flows down through one check, thence through the lower rail, thence up through the other cheek and through the top rail to a partition 9 near the point of feed, where an external pipe connection 10 with a blow-off valve 10 leads from the upper rail into the upper end portion of the body. The roof of the top rail inclines from the other end to the pipe 10 and any steam creeps along the roof and passes through the blow-off valve. The body is provided with a central baffle 11, which extends downwardly from its top to the peep hole 12 cored through the body. The water flows down one side of this baflie, rises through thelrody on the other side, and may be taken out through pipe 13 at the opposite upper corner from the inlet.

The roof of the lower rail is preferably inclined up ,wardly from its central portion in opposite directions to prevent the formation of steam pockets, Any steam collecting will creep along one of these inclined portions and rise with the water. The checks and rails are preferably provided with inwardly inclined inner v faces to assist in keying and holding the refractory brick in place, which is filled in back of the body portion in the space within the rim.

In the operation of the door, the water circulates first through the hollow rim portion, and then through the body in the manner above described. The door may be raised and lowered by suitable connections leading to lugs 14 arranged in pairs, and preferably cast integral to the top portion.

In the form of Figs. 4, 5, 6 and-7 I show the rim as consisting of four parts, instead of one part, as in the lirst form. The top rail 4 is shown as formed of a hollow casting of a length equal to the width of the door body 2; while the lower rail 5 is a hollow casting of a length equal to the width of the door plus the thickness of the cheeks 3. These cheeks are formed of castings extending upwardly from the lower rail to the top of the upper rail. The four castings are preferably formed with closed ends, and the inner faces of the top rail and cheeks are preferably inclined inwardly to key-and hold the lirebrick filling or lining which fills the space in the rear of the body portion, and between the cheeks and rails. The cavities of the cheeks and bottom rail are connected by external front pipe fittings 10; and the top portion of one cheek is connected to the. end of the top rail by a Ushaped pipe 15 having a blow-off valve 16 at its top. This blowpff valve is set at a certain pressure, so that if steam is formed it will lift the valve and blow off, when the pressure exceeds the determined limit. The other end of the upper rail is connect-ed to the door body by a similar U-shaped pipe 15, and blow-off valve 16. The hollow body is provided with a baffle 11 which extends down from its closed top preferably to the peep-hole 12, the waterllowing down on one side of the baffle, rises on the opposite side, and flows out through a top pipe connection l3.

The body may be secured to the top and bottom rails and the checks by angular lugs 6 projcctingforwardly, and preferably cast integrally with the parts, the securing bolts 7 extending through these lugs. The water enters the upper end of one check through the pipe 9, flows downwardly through the check, thence through the pipe connection into the lower rail, thence through the rail and the other pipe connection to the opposite cheek, thence through said check and the upper pipe connection to and through the top rail. From the top rail it passes into one upper corner of the door body, and thence circulates around the baffle and through the outlet.

The advantages .of my invention result from the forming of the'body separate from the cheek and rail portions. This cheek and rail portion may be made in one part, or in two or more parts; but in either case the body is cast separately thus making at least two parts, which are secured together, giving easily-made castings and a thorough water-cooling. This construction also provides for the ready detachment and replacement of a broken or burned out portion of the rim without renewing the entire door. I

A further important advantage which results from the separate construction of the body and rim portions, as abovedescribed, is found in the effects of expansion and contraction. The rim portion is subjected to greater heat, than the body portion, and is, therefore, subject to greater expansion and contraction. When the parts are formed in one piece, this expansion and contraction ofthe rim pulls upon the body portion and tends to crack it. When the parts are cast separately, the rim portion can expand and contract independentlyof the body portion.

A still further advantage is found in the increased facility which the separate construction of the parts provides for lining and relining the door with brickwork. Herctofore, it has been necessary to put this lining in place from the back or inner side. The inner walls of the rim portion are inclined to hold the bricks in place,

and when the-lining is placed from the inner side, it is very diilicult, if not impossible, to fit the bricks closely enough to the inclined walls to hold them in place. With the present construction, the lining is applied before the body is secured to the rim. The latter is laid with its inner face downward upon a fiat surface, and the bricks are inserted, and can be fitted closely to the retaining walls of the rim in working from this side. The same advantage is present in relining, as the body can be readily detached. As the relining is a frequent necessity, this advantage will be apparent to those skilled in the art. The water circulates through the rim portion before it enters the body and hence cools the parts subjected to greatest heat beforeit enters the body, which is shielded by the fire-brick lining.

The door is preferably formed either of copper or an alloy containing a high percentage, preferably 98 per cent. or above, of copper. Copper,'or this high alloy thereof, will not crack under heat, and it also enables the door to be made much lighter than where cast iron is used.

The body portion may be used alone as a water-cooled door without a lining; the form of the body and the'rim scares portion may be varied, as well as the water connections, the means for securing the parts together, &c., without departing from my invention.

I claim:

1. A furnace door composed of a hollow body portion, and 'a rim portion, the latter being separable from and detachably secured to the body portion and extending along the top and side edges at least of the body .portion, together with water circulating connections for the body portion; substantially as described.

2. A furnace door composed of a body portion, and a hollow rim portion, the latter being separable from and detachably. secured to the body portion, and extending along the'top and side edges at least,of the body portion, together with water circulating connections for the hollow rim; substantially as described.

3. A furnace door composed of a hollow body and a separate hollow, detachable surrounding rim portion, the

body fitting against the outer side portion of the rim portion; substantially as described,

4. A water-cooled door, comprising a hollow body portion, a separate hollow rim portion made in sections and detachably secured to the body portion, andwater connections between the different sections, and also between the rim portion and the body portion; substantially as described.

'5. A water-cooled door body having a lower peep hole inclosed within its body and a vertical central baflle extending down to the peep hole, a water inlet at one side of the bafiie, a water outlet at the other side and a removable hollow rim secured to the body and projecting inwardly therefrom; substantially as described.

6. A water-cooled door having a hollow body and a hollow rail, withn pipe connection between them, and a blow-off valve in the pipe connection; substantially as described.

7. A hollow water-cooled door having an upper rail with an inclined roof, and a steam outlet at the upper end of the incline; substantially as described.

8.. A hollow water-cooled door, comprising a hollow body and a separate hollow rim secured thereto, said rim having a lower rail with an inclined roof arranged to direct the steam into the cheeks; substantially as described.

9. A water-cooled door, comprising a hollow body, a surrounding hollow rim portion secured thereto by external nut and bolt connections, and water connections between the door and the rim; substantially as described.

10. A furnace door composed of a body portion and a rim portion, the latter being separable from and detachably secured to the body portion and extending along the top and side edges at least of the body portion; substantially as described.

11 A furnace door composed of a body and a separate detachable surrounding rim portion, the body fitting against the outer side portion of the rim portion; substantially as described.

In testimony whereof, I have hereunto set my hand.

LUTHER L. KNOX.

Witnesses H. M. Conwrn, JoHN MILLER. 

